The environmentally friendly nature of bamboo wood is well known, but what about the processes that turn it into those products you see on the shelves? Bamboo is actually a type of grass, and to turn it from round stalks into a uniform material that you can make something out of requires separating the fibres and gluing them together in different ways. Many other wood products use glues to turn them into a uniform and stronger material, including your standard pine plywood used in building and commonly used MDF (Medium Density Fibreboard, which can be up to 15% glue). As with everything some glues are better than others and as always there is a trade-off between cost, the environment and performance.
The most common timber glues are based on phenolic resin and urea-formaldehyde. Both contain formaldehyde (H2CO) which at high doses is toxic to humans, and a known carcinogen. Therefore formaldehyde emissions from glues need to comply with the formaldehyde emission standards for safe exposure levels. The glues are rated on the 5-level international E-scale, from E3 as the worst, to Super E-0 as the best. E0 is the level of emissions we are often exposed to as part of our natural environment. Want to know more detail about formaldehyde off-gas from products, check out this article from weemakechange.co.nz
Our very first shipment of plywood 4 years ago was made with E0 glues, which we thought was pretty good, until we learned that Super-E0 was an option! We worked with our supplier to find a suitable glue, and after a few unsuccessful trials finally ended up with our current Super-E0 adhesive. It's great to be able to continuously improve our products, as we ourselves learn more and dig deeper into each aspect of what we do.
So how can we be sure that we really have Super-E0 glue? As we are working with our plywood every day, we wanted to be sure that we weren't being exposed to high levels of formaldehyde. Engineered wood products naturally off-gas H2CO, but the process of cutting them emits much more than the background levels. We invested in a simple air quality meter, calibrated to test for airborne formaldehyde. We use it to check our incoming shipments of bamboo, and also run it regularly inside the laser cutter to measure the emissions during the cutting process.